code: def _apply_controlled_v(target_wire, control_wire):
      """Provides the circuit to apply a controlled version of the :math:`V` gate defined in
      `this <https://arxiv.org/abs/1805.00109>`__ paper.
  
      The :math:`V` gate is simply a Pauli-Z gate applied to the ``target_wire``, i.e., the ancilla
      wire in which the expectation value is encoded.
  
      The controlled version of this gate is then a CZ gate.
  
      Args:
          target_wire (Wires): the ancilla wire in which the expectation value is encoded
          control_wire (Wires): the control wire from the register of phase estimation qubits
      """
      return [CZ(wires=[control_wire[0], target_wire[0]])]
  
file_path: pennylane/pennylane/transforms/qmc.py
imports: from copy import copy
  from typing import Sequence, Callable
  import pennylane
  from pennylane import PauliX, Hadamard, MultiControlledX, CZ, adjoint
  from pennylane.wires import Wires
  from pennylane.templates import QFT
  from pennylane.transforms.core import transform
label_desc: Use image node_id 2 for calling a global function with example usage: _apply_controlled_v(target_wire, control_wire) and returns: list